The area of receptor biology is one of several in biochemistry in which an attempt is being made to understand a complex biological phenomenon at a molecular level. Those working on a variety of membrane receptors face similar problems: 1) a paucity of material on which to perform a molecular characterization; 2) an anisotropic semi-solid medium in which the critical reactions take place; 3) the need to study multiple interactions between macromolecules. It is because of these common difficulties that the FASEB Summer Conference on Receptors in 1982 and 1984 which brought together scientists from a variety of disciplines had their special usefulness. The conference planned for 1986 will continue this approach. Particular emphasis will be placed on common mechanisms of signal transduction: activation of adenylcyclase, protein kinases and phospholipase C. Additional aspects common to a variety of receptors that will be considered are regulation at the genetic and receptor level and interactions of receptors with cytoskeletal elements. In each instance special emphasis will be on studies at the molecular rather than phenomenological method.